Telephone system.



H; P. CLAUSEN. TELEPHONE SYSTEM. APPLICATION FILED MAY II. I9I5.

Patentedfiept. 5,1916.

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manner Parana or HENRY PETER CLAUSEN, F MOUNT VERNON, NEW YORK; ASSIGNOR, BY MESNE ASSIGNMENTS, T0 WESTERN ELECTRIC COMPANY, INCORYORATED, A CORPORA- TION OF NEW YORK.

TELEPHONE SYSTEIVL To all whom it may concern:

Be it known that I, HENRY PETER CLAU- snx, a citizen of the United States, residing by means of line at Mount Vernon, in'the county of Vestchester and State of-New York, have invented certain new and usefu Improvements in Telephone Systems, of which the following is a full, clear, concise, and exact description. 7 i

This invention relates to telephone terns, and particularly to systems in which means are provided for informing a calling subscriber when ringing current is applied to the line of the called subscriber.

Heretofore, various schemes have been devised for satisfying the calling party that his call is being sent as, for example, by transmitting a portion of the ringing current back over the calling subscribers line, but these schemes have proven unsatisfactory because very often the calling su'bscriber would mistake the induced ringing current upon his line for a busy tone and restore his receiver 'Withoutgiving the scriber.

In accordance i'vith this invention there is provided at a central ofiic'e a source 0t ringing current adapted to be impressed upon' a subscribers line. A signaling device is'arranged to be actuated by said ringing current, and associated with said device is a telephonic element adapted to be inductively connected to the talking strands of an operators cord circuit. A

This invention will be more clearly 'understood byreference to the accompanying.

drawing which-shows a calling subscribers station'A and a called subscribefs station B. Each of these substations are connected ircs l. Z'to a jack 3 at a central oflice. Associated with the line circuit is the customary line relay 4 line lann 5 and cutoff relay (3. A connecting cord circuit of a two-conductor type is shown having conductors H and S) terminating respectively upon the tip and ring contacts oi the answering and calling plugs 10 and ll rcspiwtivcly. in each of these conductors a condenser 12 is inserted'to inter- Specification of Letters Patent.

Patented se t, 5, rare.

Application filed May 11, 1915. Serial NOE 27,349.

cord the live pole of the battery has .con-

nection with the ring strand through the supervisory relay 1G, and the grounded pole has connection with the plug tip strand through the supervisory relay 1]. The

supervisory relays 14, 15 conjointly control supervisory relays 16 and 17 conjointly control the supervisory lamp 19 of the-calling line of the cord circuit. An operators set-is adapted to be bridged across the talkthe supervisory lamp 18 of the answering end of the cord circuit, and likeivise'the ing strands of the cord circuit by means of v a listening key 20.

Asource of ringing current 21 isadapted to be associated with the calling portion of the cord circuit by the actuation of a ringing key 22. ringer, responsive to alternating current, is arranged to be actuated by the'ringing current from the source 21.' Associated with A signaling device 23, such as a I the signaling device 23 is a telephonic eles' ment 24, connected in a manner conforming to standard practice with a transformer 25,

which is adapted to be connected to the ring side of the calling portion of the cord ci r-. cult through one of the contacts-of the ringing key When subscribers A and B are connected by inserting the answering and callingplugs, 10 and 11 respectively into the line jack 3 of each subscriber s'line, upon the operation of the ringing key ringing current is applied to the line of the called subscriber l5. Sin'iultaneous with the applicw tion ot'this ringing current to the called subscril'iefls line thesignaling device 23 is actuated. The actuation'of this devicepro duccs a tone or ringing sound which is transmitted back upon the line of theralling subscriber A, through the agency of the telephonic element 24: and the transformer The circuit of this induced tone may be traced from battery, through the secondp 65 relay 15. In the calling plug portion or the ary winding 0'2.

pressed upon the line of transformer 25, ring strand of conductor 12, out over the line and through the substation A, returning over the tip strand to ground, through the Winding of supervisory relay 15. t will be noted that as this induced current is an alternating current, it will readily pass tillOllglltl'lQ condenser 12. The calling subscriber hearing this tone Will be given the impression that he actually hears the bell of the called party being rung. This signal is so chain acterist-ically distinctive that there is little likelihood that the calling subscriber will confuse it with the ordinary time customarily transmitted back to a calling subscriber in event the line of the called party happened to be in use at the time the call is originated.

Vlhat is'claiined is:

1, In a telephone system, a calling" and a called subscribefis line terminating in line jacks at a central office, a link circuit for connecting said lines in conversation, a, source of ringing current associated with said link circuit and adapted tobe impressed upon the line of said celled subscriber, means ,ifor givin an audible signal of characteristic tone, and means for Ciillr said signal into current impulses corresponding characteristics impressed uno'i said culling subscribers line when said 1g current is impressed upon said celled subscriber-s line.

2 In a telephone system, a calling and a celled subscribers line terminating in line jacks a central (allies/,1: link circuit for connecting said lines in conversation, :1 source ing curre associated with said link c uit and a d to be inn sand celleclsuhen e1 scriber, a signaling device adapted operated by said. ringing current, honic element associated with said i mg device, and means tor-inductively necting said telephonic element with talking strands of said link circuit who the calling subscriber is given a. charm tic tone Whenever said ringing current is applied to said line. I

In a telephone system, a calling called subscribers line terminatin line jacks at a central ollice, link ci for connecting said lines in conver source of ringing current associated said linlocircuit and adapted to pressed upon the line of said call i scribcr, a ringer adapted. to be open said ringingcurrent, e telephonic associated with said ringer, and in an inductively connecting said telephonic ment with the talking strand of said circuit whereby the calling subscril .giren the sound of a bell ringing uh ringing current is applied to said i line.

4. .ln a telephone system, sul i lines. terminating at a central oiiice, :v, circuit having one end connected u" of said lines, a source of ruining means adapted to actuated to current from said s urre ugion line, source oi tone signelii and a switch operated upon act said means to connect said source signaling current to the other end link circuit,

In witness whereof, I hereunto my name this 8th day of Riley fl 

